338 HISTORY OF BRITISH ZOOPHYTES. 



wide apertures are fringed on the upper edge with four or 

 five long calcareous spines, which are easily broken off 

 when dry, and the mouth is often covered with a pearly 

 operculum. It is in all states beautiful ; but when a lens 

 is applied to it in this pearl-operculated form, it is one of 

 the finest objects of a minute nature that can anywhere be 

 seen. What human hand would not hang down in despair, 

 if required to imitate it ; and yet the great UNSEEN teaches 

 an almost invisible worm thus elegantly to fashion it. We 

 have ten fingers, and they often work wonders. Professor 

 Edward Forbes states that this little Ascidian polype has 

 from twelve to sixteen, to which we give the name of 

 teritacula. 



2. CELLULARIA TERN ATA, Dr. David Skene. 



Hab. Sent from Aberdeen, by Dr. D. Skene, to Ellis ; 

 Dr. Fleming's were from Zetland; mine were from Lady 

 Keith Murray, Stonehaven, and from Mr. Bean, of Scar- 

 borough, at which latter place it is not rare on corallines, 

 and sometimes attached to shells. Peterhead, abundant, 

 Mr. Peach. 



It is about an inch in height, branching dichotomously ; 

 the cells enlarge gradually in breadth towards the top, and 

 are armed above with two or three short spines. It takes 



